Acoustics Course Research Articles

Development of an online undergraduate course in acoustics at the Berklee College of Music

Between 125 and 150 students take an introductory course in acoustics each semester at the Berklee College of Music in Boston, MA. As the popularity of acoustics has grown (owing in part to a new minor in acoustics and electronics) limited classroom facilities have made it difficult to meet the demand for sections of the introductory class. Development is nearly complete on a fully online version of the course that will be offered beginning in 2014. This paper will examine the curriculum, development of media assets, and various hurdles in the development process.

A laboratory investigation of the effect of trumpet mouthpieces in an introductory musical acoustics course

In our introductory musical acoustics course for non-science majors, a major goal of the course is to introduce students to the principles of scientific thinking and investigation. Many students have preconceived ideas or beliefs about factors influencing the sounds produced by musical instruments. It is the role of the instructor to help students frame their ideas into scientifically testable experiments, which can be conducted in the laboratory. In our course, we have designed a laboratory activity to challenge students to explore the role of the mouthpiece of brass musical instruments. A parametric model of a trumpet mouthpiece is customized by students in order to investigate the effects of changing mouthpiece geometry on the trumpet acoustics. The models are manufactured on a 3D printer and used in the laboratory to make input impedance measurements. Students compare their quantitative results to the qualitative conceptions they held before completing the laboratory investigation.

Computer modeling as teaching tool in underwater acoustics

One of the challenges of teaching acoustics is to bridge the gap between theory and application. However, laboratory experiments are often too difficult or costly particularly for large-scale phenomena such as ray bending in ocean acoustics. Computer modeling is a low cost, easily accessible way for students to visualize acoustic phenomena without the overhead of laboratory experiments. In the underwater acoustics course at the University of Texas at Austin, students develop an acoustic modeling suite throughout the course culminating in a code to solve the sonar equation for a target in a shallow water environment. Beginning with simple attenuation, students model rays bending due to sound speed profiles, modes, both propagating and leaky, reverberation, target scattering, array steering, and signal processing. Each component builds on previous code and, at the end of the course, the student has a coherent collection of underwater acoustic modeling tools.

Genealogy of Kenneth N. Stevens and the Speech Communication Group at the Massachusetts Institute of Technology

Ken often told a story to his advisees, illustrating how a seemingly insignificant event could change the course of a life. When Ken began his graduate studies at MIT, Leo Beranek learned that he had taken an acoustics class as an undergraduate and recruited him as a teaching assistant. Beranek was doing research on speech acoustics, and soon Ken was one of his research assistants. Thus, Ken’s decision to take an undergraduate acoustics course led him to his lifetime of work in speech communication, in which he found boundless pleasure. After completing his Sc.D. in 1952, Ken joined the MIT Faculty. His first doctoral student was James Flanagan. He supervised at least 31 more doctoral students and scores of post-doctoral, masters, undergraduate, and visiting students over 53 years. Ken collaborated with MIT colleagues (e.g., Morris Halle and Jay Keyser, Linguistics Dept.) and many researchers well beyond 77 Massachusetts Ave (e.g., Gunnar Fant, KTH, Sweden). His interest in how the physics of the vocal tract interacts with contrastive phonological categories unequivocally changed the field of Speech Communication, as well as the lives of his many students and collaborators who have gone on to establish their own laboratories and research programs.

Time-frequency analysis for acoustics education and for listening to whales in the Gulf of Mexico

Time-frequency plots continue to be used in many varied applications. One particularly advantageous use is in acoustics courses accessible to non-science majors, students who are often frightened of mathematics and/or physics. All musicians as well as many others can read and understand music scores (time-frequency plots). Time-frequency plots are extremely useful in explaining the differences in timbre of the same pitch coming from different musical instrument families, from individual instruments themselves, and from different human voices. Examples are given from the first of a UNO two-semester sequence on the Physics of Music (textbook by Rossing!). The second semester of this sequence includes recording and reproduction of music, and time-frequency plots are again very useful. Investigation of acoustic signals for research also benefits from the use of time-frequency plots. The study of marine mammals is enhanced by analysis of underwater acoustic recordings. Examples of both the sounds of and the time-frequency plots for sperm whale clicks in the northern Gulf of Mexico are presented. Seismic airgun shots from oil industry exploration can be heard on the recordings as well as the whale clicks.

Techniques used to promote active learning in an undergraduate architectural acoustics course

The five-year undergraduate architectural engineering (AE) program at Penn State requires all students to take an introductory course in architectural acoustics (AA) and for most students in the program, no further AA courses are required. As a result, it is very important to capture the students’ interest early on in the course and use strategies that will improve long-term retention of the material. A number of techniques were used to improve student engagement with the introductory AA course that had an enrollment of 94 students. The first homework assignment was to summarize a recent magazine article in any area of acoustics, which allowed the students to immediately see a real-world application of the subject. During lecture periods, students were encouraged to participate through the use of personal response devices, also known as “clickers.” Several different types of clicker questions were used, including review questions from the preceding lecture, questions to prompt participation during the presentation of example problems, and conceptual questions. The results from the multiple choice clicker questions are immediately displayed, which provides useful feedback to both the students and the instructor. Some hands-on activities during the practicum periods were also incorporated to reinforce the content from the lectures.

Making music: A serious attempt at designing new instruments by undergraduate students

We describe a course in musical acoustics that required undergraduate students to design and build unique musical instruments, compose music for ensembles of them, and then perform the compositions in a public concert. Unlike most courses in musical acoustics which require the students to build home-made instruments as a final project, the construction of the instrument and composing original music were the primary goals of the course. The instruments were required to be artistic, visually interesting and play a pitch collection from the Western scale. We will describe the challenges and successes, show examples of the instruments, and review the lessons learned.

Laboratory Investigation of Noise-Canceling Headphones Utilizing “Mr. Blockhead”

While I was co-teaching an introductory course in musical acoustics a few years ago, our class investigated several pieces of equipment designed for audio purposes. One piece of such equipment was a pair of noise-canceling headphones. Our students were curious as to how these devices were in eliminating background noise and whether they indeed block low-frequency sounds as advertised.

Teaching acoustics at architect students using digital tools

At the School of Architecture, Lund University Sweden, courses are taught in different ways. A large part of the education during year one and two is held as “studios,” doing creative (individual) project work. Usually acoustics courses rather correspond to the traditional engineering education style, using lectures, exercises, small project works, and final written examination. The problem is that many students do not know how to use the gathered information in their creative works. The aim of the study covered by this paper was to improve upon the existing teaching/learning of the fundamental acoustics principles scheme by introducing new methodologies. In order to achieve our goal, we gave the students two different assignments: In the first assignment, the students had to produce short educational movies to explain and teach acoustics principles to their peers. In the second assignment, they should implement the new knowledge gathered in the first assignment into their individual creative projects.

Nachhaltigkeit beim Bibliotheksbau

Abstract The 16th seminar of the LIBER Architecture Group, which took place in Prague in 2012, offered its participants a range of different topics dealing with library architecture. Special focus of the seminar was the reuse and refurbishment of existing buildings with regard to issues of sustainability. The presentations included general principles of the planning process in connection with the functions and roles of libraries within urban planning. They also informed on current developments in teaching and research at European universities. Projects were presented, which showed energy saving planning approaches as well as the reconstruction and complete reorganization of existing buildings in order to adapt them to current demands of library buildings. In addition, a crash course in acoustics was provided. Libraries as learning spaces were not only shown in the presentations during the seminar, but could be explored during the visits of the Technical National Library in Prague as well as in other Czech libraries. The program of the conference concluded with presentations, which focused in particular on the preservation of collections.

Introducing the concept of resonance to non-science majors in a musical acoustics class

Understanding the concept of resonance is one of the most important goals for a student in a musical acoustics course to achieve. In our musical acoustics course students examine the standing wave behavior of simple one-dimensional systems such as stretched strings and pipes with open ends or one closed end. The concept is integral to the discussion of how nearly all musical instrument work, but it is also a difficult concept for many students to understand. In our class, we discuss how looking at the boundary conditions of the systems we examine in class can be applied to predict what the resonant frequencies of the system are.

Use of pre-class quizzes to promote active learning in acoustics

Classroom instruction can be inefficient or ineffective when students do not come to class prepared. One strategy to engage students prior to class is the use of pre-class quizzes. One pedagogical method developed for introductory courses by physics education researchers is pre-class “just-in-time-teaching” quizzes. As a variation on that idea, pre-class learning activities have been used with great success in the general education acoustics course at Brigham Young University (BYU). However, such methods are not often applied at the advanced undergraduate and graduate levels. This paper reviews some of the findings from the introductory course efforts and then describes the implementation of pre-class quizzes for two advanced acoustics courses at BYU. Two lessons learned thus far are 1) the questions, which have a free-response format, must be carefully constructed so that the instructor can gauge student understanding, and 2) when successfully implemented, the quizzes can provide an effective framework for a class discussion of a topic, rather than a lecture with little to no participation.

Acoustic tweets and blogs: Using social media in an undergraduate acoustics course

Each fall, the author teaches an undergraduate architectural acoustics course to around 40 third-year architectural engineering students at the University of Nebraska. Beginning in 2011, a social media component was introduced to explore the use of this technology and how it may supplement the students’ learning experience. Students were given an opportunity to receive extra credit by using twitter and/or blogging about course material using a set hashtag (#AE3300) or through the course website. Results were positive, and the author will discuss pros and cons that she has experienced in adding this social media component. Suggestions for future implementations and examples of student participation will be presented.

Fostering research in a general education acoustics course

The general education science course often is the last science course an undergraduate takes. Liberal arts core requirements may include the goal that students come to understand or appreciate the nature of science and its impact on society. Incorporating research experience may be desirable, but has its challenges in a course for the non-major. A basic toolkit for student inquiry gives the capabilities for sound editing and analysis, filtering, sound level monitoring, sound and music synthesis, vowel and speech analysis, musical instrument design, and room acoustics analysis. These tools are available as low cost or free software. A course design compromise must be reached between delivery of content and support of student inquiry. However, a class of forty pursuing independent research projects in acoustics makes a rewarding experience for both instructor and students!

Providing interactive engagement in introductory acoustics through design-intensive laboratories

More than three decades worth of education research has shown with overwhelming evidence that the best way for students to learn is to be actively engaged in the classroom rather than passively taking in material delivered from an instructor. Although the reform of introductory classes has been widely adopted by many instructors, the implementation of reformed introductory laboratory curricula has not been as widely adopted. In our introductory acoustics course, students complete design-intensive labs where much of the instruction has been stripped away. The emphasis on student-driven experiment design and analysis is intended to provide a more scientifically authentic experience for students. The course is taught using an integrated lecture and laboratory approach. An overview of the laboratory framework and example laboratory activities used in our introductory acoustics class will be presented.

Teaching graduate level acoustics courses to a blended enrollment of resident and distance education students

The Graduate Program in Acoustics offers courses leading to the M.Eng. in Acoustics online through Penn State’s World Campus. The current method of course content delivery is to live-stream (with digital video archive) lectures to a blended student audience consisting of about 10-15 resident students physically present in the classroom and another 15-20 students at a distance who may be watching the class live, or who may be viewing the archived recording afterward. This paper will explore several issues involving the engagement of this blended audience of students. How does one encourage and enable students with a broad range of backgrounds, interests, and physical locations to engage with the topic material? How does one foster collaboration and interaction between distance students and the teacher and between resident and distance students? How does one manage office hours, help sessions, group projects, experiments, and student presentations for a blended student audience? Current practice and personal experiences from our faculty will be shared, and ideas from the audience will be welcomed.

Teaching musical acoustics with clickers

Musical acoustics is a well-proved avenue for teaching scientific concepts to students whose fields of study and interests are far removed from any science. In recent years the Michigan State course in musical acoustics has benefited greatly from using clickers. Frequent clicker questions (1 point for any answer; 2 points for the correct answer) promote attendance and help maintain a lively, interactive classroom environment, even for a large lecture class. Nobody sleeps when clicker points are on the line. Students are encouraged to discuss responses to clicker questions among themselves before answering, and the response protocol allows students to change their responses at any time before the polling is closed. Musical acoustics lectures include many demonstrations that can be presented as experiments requiring students to predict the result in advance using their clickers. “No-count” or “all-good” clicker questions can be used to determine student responses to perceptual experiments, and the feedback from the scoring algorithm gives the answer and the inevitable variability. Most important, responses to clicker questions give an instructor instant feedback about whether new lecture material has been understood. To use clickers in this way requires flexible instruction and spontaneous generation of new clicker questions.

Theoretical acoustics course for postgraduates in Naning University

There is a one academic year theoretical acoustics course for postgraduate students in the Department of Acoustic Science and Engineering of Nanjing University. The course introduces the physical principles and mathematical methods for acoustics in fluids, and the main objective is to deepen understanding of acoustical principle for postgraduate students in the field of acoustics following their undergraduate fundamental acoustics course. The contents include acoustic waves in ideal fluids, acoustic radiation in infinite space, acoustic scattering and diffractions, propagation and radiation of acoustic waves in dust, acoustic fields in enclosed space, acoustic waves in dissipative fluids, acoustic waves in layered fluid, acoustic waves in moving fluids, propagation of acoustic waves with finite amplitude, and effects generated by acoustic waves with finite amplitude. More details can be found in the book title “Principle of Acoustics in Fluids” published by Science Press in China in 2012.

Acoustical education in architectural engineering program at the University of Nebraska

An increasing number of schools are offering Architectural Engineering (AE) programs; currently there are 20 schools across the United States. However, only few of these AE programs include acoustics as a main option in their curricula. A comprehensive review of U.S. graduate programs in a report of “Technology for a Quieter America” by the United States National Academy of Engineering found that there is not sufficient training for students in acoustics in the U.S. This presentation will review the Nebraska Acoustics Group, housed within the AE program at the University of Nebraska which began in 1998. To cope with the needs, students could study acoustics within any of our five engineering degree programs (BSAE, MAE, MEng, MS, and PhD). There are currently two AE faculty out of 13 who focus in acoustics at Nebraska, and the program regularly offers at least six recurring acoustics courses. Descriptions of the acoustics courses, the research interests of the Nebraska Acoustics Group, and where our gradua...

University of Hartford undergraduate acoustical engineering programs and teaching philosophy

The University of Hartford is a small private institution that consists of seven schools and colleges, and is located in West Hartford, Connecticut, USA. A more detailed overview of the acoustical engineering curriculum and laboratory facilities will be discussed. Graduating high school seniors who wish to pursue the study of acoustical engineering at the University of Hartford have two ABET-accredited program options: (1) the Bachelor of Science in Mechanical Engineering (BSME) with Acoustics Concentration and (2) the interdisciplinary Bachelor of Science in Engineering (BSE), Acoustical Engineering & Music, which requires acceptance into the University's music conservatory, The Hartt School. These acoustical engineering programs are within the Mechanical Engineering Department, which is part of the College of Engineering, Technology and Architecture. Both programs require a number of theoretical courses in acoustics and vibrations. These theoretical courses are balanced with hands-on real-world design projects and a number of these projects are done for non-profit organizations to expose our students to service learning. Students participate in these industry-sponsored full-semester design projects at both the sophomore (2nd year) and senior (4th year) levels. As a result, students leave the program with a solid foundation of both the theory and real-world applications of acoustical engineering.